Luna, with her connection to the moon and her magic related to the night. And Supernova, who could be a pony from a far - off land or even a new creation within the fanfiction world. They are likely to be at the center of the story, driving the plot forward with their actions and interactions. For example, their different personalities might clash at first, but then they learn to work together as the story progresses.
One interesting storyline could be Luna and Supernova teaming up to save Equestria from a new and powerful dark force. They might use their combined magic to overcome the threat.
One common theme could be the anticipation and excitement in Equestria. The ponies might be looking forward to the new arrival. Another theme could be Luna's own journey during pregnancy, like dealing with physical and emotional changes. And sometimes, there might be a theme of unity as the ponies come together to support her.
There are likely some out there. You can start by checking popular fanfiction websites like FanFiction.net or Archive of Our Own. However, the concept of Luna being pregnant in fanfiction can vary greatly in terms of the storylines, from exploring new magical aspects in Equestria due to her condition to how the other ponies react to this big change in Luna's life.
Luna might be initially cautious around Godzilla. Given her role as a princess in Equestria, she would likely try to assess if Godzilla is a threat. Godzilla, on the other hand, might be confused by the new environment. Eventually, Luna could use her magic to communicate with Godzilla, perhaps on a telepathic level. They would then start to understand each other's motives and find common ground, like protecting their respective homes from danger.
The theme of forgiveness is also quite common. Luna, being a more benevolent character, might be in a position to forgive Sombra for his past wrongdoings. This can lead to some really emotional and character - building moments in the fanfiction. Also, the theme of magic and its consequences is often explored. How their magic affects themselves and the world around them is a big part of many of these stories. For example, Sombra's dark magic might have unforeseen consequences that Luna has to deal with, or vice versa.
Growth and self - discovery also feature frequently. Both Twilight and Luna can grow as characters in fanfictions. Twilight might learn more about leadership from Luna, and Luna could discover new aspects of herself through her interactions with Twilight. This could be related to their understanding of their powers, their place in Equestria, or their relationships with other ponies.
One interesting fanfiction could be about Celestia and Luna's early days ruling Equestria together. It might explore how they divided their duties and overcame challenges. For example, they had to deal with the first signs of Discord's chaos. Another could be a story where they swap roles for a day to understand each other's responsibilities better. And there could also be a fanfic that focuses on their relationship with Twilight Sparkle, as she learns from them.
I think [Author X] is really good. Their works often explore the more emotional side of Celestia and Luna's relationship. They write in a way that makes you care about the characters on a deeper level. There's also [Author Y] who is known for their creative takes on Celestia and Luna. Their fanfictions can be really out - of - the - box, like imagining Celestia and Luna as ordinary ponies for a day.
The main characters are obviously Celestia and Luna. Celestia is the benevolent and wise ruler of Equestria, associated with the sun. Luna, on the other hand, is the princess of the night. In the fanfiction, they are likely to be central to whatever stories are being told, whether it's about their relationship as sisters, their ruling duties, or their adventures.